Field of the Invention
The invention relates to a web infeed device for rotary printing presses and, more particularly, to such a device for guiding one or more webs through all the components of the rotary printing press.
U.S. Pat. No. 4,987,830 discloses a web infeed device for rotary printing presses. In this device, many guide rails are mutually aligned in rows along the various web paths. A linear element guidable along a previously defined web path is disposed in the guide rails. A lever is mounted on the linear element and, on a side thereof facing towards the web, is provided with a snap closure, from which a new web which is to be inwardly threaded can be suspended and thereby pulled through the press. The linear element is moved by a plurality of drive stations disposed along the guide rails. The length of the linear element is selected so that it just exceeds the spaced distance between any two adjacent drive stations.
The published Japanese patent document JP Hei 2-265 848 relates to a device for infeeding paper for a rotary printing press. In this construction, the web to be infed is guided from a paper-roll support through the printing units of the press to a folding apparatus. Along the web path defined by the components of the press, a guide path is provided. An infeed or insertion element for inserting the paper web has a strip or band-shaped construction and is provided with regularly arranged openings or bumps on at least one side thereof. The openings may also extend all the way through the strip or band-shaped infeed element. A take-up or receiving section for the starting end of the material to be fastened and in-threaded is also provided on the strip or band-shaped infeed or insertion element. A drive system made up of a plurality of drive stations engages in the openings or with the bumps on the strip or band-shaped infeed or insertion element in order to guide the infeed or insertion element by rotation.
Moreover, a device for infeeding or inserting webs of material in rotary printing presses has previously become known from German Patent 2 402 768. In this embodiment, a flexible, finite infeed or insertion element is provided having a length which is somewhat greater than the spacing between adjacent drive elements, a plurality of which are provided for moving the infeed or insertion element in guides and shunts along an infeed or insertion path. Along the infeed or insertion path, scanners or sensors are provided for turning on whichever drive element is needed and simultaneously turning off whichever drive element is no longer needed, the scanners or sensors being actuatable by the infeed or insertion element.